summaryrefslogtreecommitdiffstats
path: root/kernel
diff options
context:
space:
mode:
authorIngo Molnar <mingo@elte.hu>2007-08-24 20:39:10 +0200
committerIngo Molnar <mingo@elte.hu>2007-08-24 20:39:10 +0200
commit71fd37146385c8255bfd370f33ca81fe8c81e5a5 (patch)
tree63ef23a5290202c5619d7e3f3f9428d29d5b7db1 /kernel
parent7c6c16f354cde4a48bd305b2587fc78257bcb936 (diff)
downloadblackbird-op-linux-71fd37146385c8255bfd370f33ca81fe8c81e5a5.tar.gz
blackbird-op-linux-71fd37146385c8255bfd370f33ca81fe8c81e5a5.zip
sched: remove HZ dependency from the granularity default
remove HZ dependency from the granularity default. Use 10 msec for the base granularity, 1 msec for wakeup granularity and 25 msec for batch wakeup granularity. (These defaults are close to the values that the default HZ=250 setting got previously, and thus it's the most common setting.) Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/sched.c2
-rw-r--r--kernel/sched_fair.c13
2 files changed, 7 insertions, 8 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 96e9b82246d2..e95ff22ed174 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -4923,7 +4923,7 @@ static inline void sched_init_granularity(void)
if (sysctl_sched_granularity > gran_limit)
sysctl_sched_granularity = gran_limit;
- sysctl_sched_runtime_limit = sysctl_sched_granularity * 8;
+ sysctl_sched_runtime_limit = sysctl_sched_granularity * 5;
sysctl_sched_wakeup_granularity = sysctl_sched_granularity / 2;
}
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index b5270dc98bef..6b0974c3fb67 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -19,7 +19,7 @@
/*
* Preemption granularity:
- * (default: 2 msec, units: nanoseconds)
+ * (default: 10 msec, units: nanoseconds)
*
* NOTE: this granularity value is not the same as the concept of
* 'timeslice length' - timeslices in CFS will typically be somewhat
@@ -31,18 +31,17 @@
* number of CPUs. (i.e. factor 2x on 2-way systems, 3x on 4-way
* systems, 4x on 8-way systems, 5x on 16-way systems, etc.)
*/
-unsigned int sysctl_sched_granularity __read_mostly = 2000000000ULL/HZ;
+unsigned int sysctl_sched_granularity __read_mostly = 10000000UL;
/*
* SCHED_BATCH wake-up granularity.
- * (default: 10 msec, units: nanoseconds)
+ * (default: 25 msec, units: nanoseconds)
*
* This option delays the preemption effects of decoupled workloads
* and reduces their over-scheduling. Synchronous workloads will still
* have immediate wakeup/sleep latencies.
*/
-unsigned int sysctl_sched_batch_wakeup_granularity __read_mostly =
- 10000000000ULL/HZ;
+unsigned int sysctl_sched_batch_wakeup_granularity __read_mostly = 25000000UL;
/*
* SCHED_OTHER wake-up granularity.
@@ -52,12 +51,12 @@ unsigned int sysctl_sched_batch_wakeup_granularity __read_mostly =
* and reduces their over-scheduling. Synchronous workloads will still
* have immediate wakeup/sleep latencies.
*/
-unsigned int sysctl_sched_wakeup_granularity __read_mostly = 1000000000ULL/HZ;
+unsigned int sysctl_sched_wakeup_granularity __read_mostly = 1000000UL;
unsigned int sysctl_sched_stat_granularity __read_mostly;
/*
- * Initialized in sched_init_granularity():
+ * Initialized in sched_init_granularity() [to 5 times the base granularity]:
*/
unsigned int sysctl_sched_runtime_limit __read_mostly;
OpenPOWER on IntegriCloud